I feel like that falls into three camps:

• Stability issues. That's really from the engine or similar, not the scripts. Starfield did well here. Fallout: New Vegas tended to have problems that accumulated for me over the course of a given game.

• Performance issues. Fallout: New Vegas and Fallout 4 both took increasingly longer to load the further into the game one was. I don't recall Fallout 76 or Starfield doing this. Up until Starfield, the 3D games had various situations where one could see graphical artifacts.

• Scripting issues, weird interactions between quests, etc. That's been a problem for the whole Fallout series, including the isometric games -- lots of scripts that can interact in weird ways. I even managed to break one Starfield mission last time I played, though fortunately could recover by restoring an earlier save, and that's been pretty solid.